The current studies addressed two questions regarding early social behaviour in children with Autism Spectrum Disorders (ASD) that have not yet been directly explored. In Study 1 we examined the hypothesis that impaired imitation in this group may reflect a diminished social motivation to engage, rather than a core deficit in imitation. Young children with and without ASD engaged in imitation tasks during which controlled manipulations of reward (social and non-social) were administered for target behaviours. Children with ASD displayed increased levels of imitation with the incentive of an external reward in comparison to when this reward was absent. There was no differential impact of social versus non-social rewards. Typically developing (TD) children performed similarly, irrespective of whether or not reward was administered. We suggest that young children with ASD may be capable of imitating when appropriate incentives are present. Study 2 explored the breadth of social challenges faced in young children with ASD by examining a later-developing domain of social functioning that may be compromised by early social difficulties. We explored the tendency of children with ASD to engage in helping, sharing, and comforting behaviour in situations where the need for the prosocial behaviour was displayed and in perceptually similar situations where the need was absent. Children with ASD displayed low levels of helping and sharing, but provided comfort at levels consistent with TD children. For both comforting and sharing, children with ASD successfully discerned situations where a need was present from when it was not and adjusted their behaviour accordingly. We suggest that children with ASD may require different ‘conditions’ to engage in social behaviours at the same level as their TD peers and suggest future research to this end.